<template>
    <div>
        <!--面包屑导航-->
        <el-breadcrumb separator-class="el-icon-arrow-right">
            <el-breadcrumb-item :to="{ path: '/' }">首页</el-breadcrumb-item>
            <el-breadcrumb-item>商品管理</el-breadcrumb-item>
            <el-breadcrumb-item>商品分类</el-breadcrumb-item>
        </el-breadcrumb>

        <el-card>
            <el-row>
                <el-col>
                    <el-button type="primary" @click="showAddCateDialog">添加分类</el-button>
                </el-col>
            </el-row>
            <!--表格-->
            <tree-table class="marginTop"
                :data="cateList"
                :columns="columns"
                :selection-type="false"
                :expand-type="false"
                :show-index="true"
                index-text="#"
                border
                :show-row-hover="false"
                >
                <template slot="isOk" slot-scope="scope">
                    <i class="el-icon-success lightgreen" v-if="scope.row.cat_deleted===false"></i>
                    <i class="el-icon-error red" v-else></i>
                </template>

                <template slot="order" slot-scope="scope">
                    <el-tag size="mini" v-if="scope.row.cat_level===0">一级</el-tag>
                    <el-tag size="mini" type="success" v-else-if="scope.row.cat_level===1">二级</el-tag>
                    <el-tag size="mini" type="warning" v-else>三级</el-tag>
                </template>

                <template slot="opt" >
                    <el-button size="mini" type="primary" icon="el-icon-edit" >编辑</el-button>
                    <el-button size="mini" type="danger" icon="el-icon-delete">删除</el-button>
                </template>
            </tree-table>

            <!--分页-->
            <el-pagination
                    @size-change="handleSizeChange"
                    @current-change="handleCurrentChange"
                    :current-page="queryInfo.pagenum"
                    :page-sizes="[1,2,5,10]"
                    :page-size="queryInfo.pagesize"
                    layout="total, sizes, prev, pager, next, jumper"
                    :total="total">
            </el-pagination>
        </el-card>

        <el-dialog
                title="添加分类"
                :visible.sync="addCateDialogVisible"
                width="30%"
                @close="addCateDialogClosed"
            >
            <!--内容区域-->
            <el-form :model="addCateForm" :rules="rules" ref="addCateFormRef" label-width="100px">
                <el-form-item label="分类名称" prop="cat_name">
                    <el-input v-model="addCateForm.cat_name" ></el-input>
                </el-form-item>
                <el-form-item label="父级分类" >
                    <el-cascader
                            expand-trigger="hover"
                            :options="parentCateList"
                            :props="cascaderProps"
                            v-model="selectedKeys"
                            @change="parentCateChanged"
                            clearable
                        >
                    </el-cascader>
                </el-form-item>
            </el-form>

            <!--底部区域-->
            <span slot="footer" class="dialog-footer">
                <el-button @click="addCateDialogVisible = false">取 消</el-button>
                <el-button type="primary" @click="addCate">确 定</el-button>
            </span>
        </el-dialog>

    </div>
</template>

<script>
    export default {
        name: "Cate",
        created(){
            this.getCateList();
        },
        data(){
            return{
                cateList:[],
                total:0, // 总数据条数
                // 查询条件
                queryInfo:{
                    type:3,
                    pagenum:1,
                    pagesize:5
                },
                // table 的列的定义
                columns:[
                    {
                        label:'分类名称',
                        prop:'cat_name',
                    },
                    {
                        label:'是否有效',
                        type:'template',
                        template:'isOk'
                    },
                    {
                        label:'排序',
                        type:'template',
                        template:'order'
                    },
                    {
                        label:'操作',
                        type:'template',
                        template:'opt'
                    }

                ],
                // 控制添加分类对话框的显示与隐藏
                addCateDialogVisible:false,
                addCateForm:{
                    cat_name:'',  // 将要添加的分类的名称
                    cat_pid:0,  // 父级分类的id
                    cat_level:0,  // 分类层级
                },
                rules:{
                    cat_name:[
                        {required:true, message:'请输入分类的名称',trigger:'blur'},
                    ]
                },
                parentCateList:[],
                cascaderProps:{
                    value: 'cat_id',
                    label: 'cat_name',
                    children:'children',
                    checkStrictly:true,
                },
                selectedKeys:[]
            }
        },
        methods:{
            // 获取商品分类数据
            async getCateList(){
                const {data:res} = await this.$http.get('categories',{params:this.queryInfo});
                if(res.meta.status!==200){
                    return this.$message.error('获取商品分类失败');
                }
                this.cateList=res.data.result;
                this.total = res.data.total;
            },
            // 监听 pagesize 的改变
            handleSizeChange(newSize){
                this.queryInfo.pagesize=newSize;
                this.getCateList();
            },
            // 监听pagenum 改变
            handleCurrentChange(newPage){
                this.queryInfo.pagenum=newPage;
                this.getCateList();
            },
            // 点击按钮，展示添加分类的对话框
            showAddCateDialog(){
                // 获取父级分类列表
                this.getParentCateList();
                this.addCateDialogVisible=true;
            },
            // 获取父级分类的列表
            async getParentCateList(){
                const {data:res} = await this.$http.get('categories',{params:{type:2}});
                if(res.meta.status!==200){
                    return this.$message.error('获取父级分类数据失败');
                }
                this.parentCateList=res.data;
            },
            // 父级id 发生改变时
            parentCateChanged(){
                // 如果selectedKeys 数组中的 length 大于 0，证明选中了父级分类
                // 否则，就表明没有选中父级分类
                if(this.selectedKeys.length > 0){
                    // 父级分类的id
                    this.addCateForm.cat_pid = this.selectedKeys[this.selectedKeys.length-1];
                    this.addCateForm.cat_level = this.selectedKeys.length;
                }else{
                    this.addCateForm.cat_pid=0;
                    this.addCateForm.cat_level=0;
                }
            },
            addCate(){
                this.$refs.addCateFormRef.validate(async valid =>{
                    if(valid){
                        const {data:res} = await this.$http.post('categories',this.addCateForm)
                        if(res.meta.status !== 201) {
                            return this.$message.error('添加分类失败');
                        }
                        this.$message.success('添加分类成功！');
                        this.getCateList();
                        this.addCateDialogVisible=false;
                    }
                })
            },
            addCateDialogClosed(){
                this.$refs.addCateFormRef.resetFields();
                this.selectedKeys=[];
                this.addCateForm.cat_level=0;
                this.addCateForm.cat_pid=0;
            }
        }
    }
</script>

<style scoped>
    .lightgreen{
        color:lightgreen;
    }
    .red{
        color:red
    }
    .marginTop{
        margin-top: 15px;
    }
    .el-cascader{
        width: 100%;
    }
</style>